This invention relates to optical coin counting mechanisms for coin dispensers such as those employed in gaming machines. More particularly, the present invention relates to optically isolated coin counting apparatus that resists tampering.
In gaming machines such as slot machines, coin hoppers store coins for the eventual payout. During payout, a mechanism delivers coins from the hopper to a hopper exit for collection by the player. As some winning combinations result in bigger payouts than others, the number of coins delivered from the hopper to the player must be precisely monitored. This is the role of a coin counting mechanism.
While there are a variety of available mechanisms for counting coins, optical detection devices are very widely used and are of most interest in the context of the present invention. In these devices, each coin that passes from the hopper during payout triggers a change in the intensity detected in the optical mechanism. One widely used optical coin counting mechanism now will be described with reference to FIG. 1.
As shown in FIG. 1, an optical coin counting mechanism 2 includes an optic cover 4 which houses an optical detector 6 having a light source 8 and a light intensity detector 10. Attached to optical detector 6 is wiring 12 for providing power and ground to the light source and light intensity detector. Wiring 12 also includes a signal line for transmitting signals from the light intensity detector 10 to appropriate processing electronics. Optical detector 6 includes an arm 14 which includes a threaded hole for receiving a screw 16 mounted through optic cover 4. Screw 16 holds optical detector 6 in place within optic cover 4. Both optic cover 4 and optical detector 6 may be made from molded plastic for example.
The optical detector 6 is mounted to an actuator mount 18 through a threaded hole 20. In this manner, the optic cover covers the optical detector 6 and a back portion of the actuator mount 18. Actuator mount 18 includes a mounting shaft 22 which engages an actuator 24. The actuator is pivotally mounted on mounting shaft 22 via a torsion spring 26, a washer 28 and an E-ring 30 (to prevent the actuator from sliding off the shaft). Actuator 24 includes a deflection arm 32 and a flag 34. Flag 34 is positioned near the optical detector 6 such that when the actuator 24 pivots about shaft 22, the flag moves between light source 8 and light intensity detector 10.
During operation, coins are passed from a gaming machine hopper over deflection arm 32. Each coin so transported, forces arm 32 upward so that the entire actuator 24 pivots about shaft 22. After a coin has exited the hopper, deflection arm 32 is forced downward back to its original position by torsion spring 26. Also, when actuator 24 rotates in response to a coin passing, flag 34 is directed between light source 8 and light intensity detector 10. This causes optical detector 6 to report a reduction in light intensity. Upon return of actuator 24 to its starting position (after the coin has exited the hopper), flag 34 moves away from optical detector 6 and intensity detector again reports a normal light intensity. Thus, each coin passing event is associated with a temporary reduction in intensity reported by intensity detector 10. In this manner, the coins passing from the hopper to the hopper exit can be counted.
While rotary-optic coin counting systems, such as that illustrated in FIG. 1, have found widespread acceptance, recently some nefarious individuals have attempted to defeat the optical mechanisms by fooling the optical detector into believing that no coins are being delivered when in fact numerous coins are being delivered. These individuals insert a small but highly intense light source, such as a small quartz lamp, into the gaming machine at an orientation which floods the light intensity detector with light, thereby preventing the detector from detecting light intensity reduction events associated with passing coins. Typically, the person trying to cheat the machine inserts the light source through the coin exit chute of the gaming machine while casino personnel are not observing. Obviously, this is a serious concern of casinos and gaming machine manufacturers alike. Accordingly, coin counting mechanisms able to completely resist such attempts to defeat the optical system would generally have wide appeal to the gaming industry.